Flashcards
22 Introduction to the Respiratory System
Flashcards do conjunto (37)
- 1What are five functions of the respiratory systemgaseous exchange
acid-base balance
phonation
warming, humidification, filtration of gas
defense against airborne pathogens - 2What are the divisions of the respiratory systemnon-respiratory
upper respiratory tract
-oro-pharynx and larynx
lower respiratory tract
-conducting airways
respiratory regions
-alveoli and terminal bronchioles - 3What is the pharynx?medical name for the throat
divided into 3
-oropharynx
-nasopharynx
-laryngopharynx - 4What is the oropharynx?part of the throat just behind the mouth
-third back of tongue
-soft palate (the soft area at the back of the roof of the mouth)
-tonsils
-tonsillar pillars (two ridges of tissue in front of and behind the tonsils)
-back wall of the throat - 5What is the larynx also known as? What three things is it involved in? What does it contain?voice box
production of sound
protection of trachea against food aspiration
manipulation of pitch and volume
vocal chords
-essential for phonation
-found just below where the tract of the pharynx splits into the trachea and oesophagus - 6What comprises the upper respiratory tract? What comprises the lower respiratory tract?mouth, pharynx, larynx
trachea, bronchial tree - 7Describe four main structural features of lungstop of lung = apex
bottom of lung = base
three lobes in RL and two lobes in LL
oblique fissure running lateral to medial diagonally - 8How many times does the airway tree divide23 times
-conducting airways = first 16 divisions
-respiratory zone = last 7 divisions - 9How many alveolar ducts are there in each lung?about 2^21
so approx. 4,000,000
each duct divides into many terminal sacs, each containing many alveoli - 10Where does gas exchange take place? What's the surface area of the lung alveoli?alveolar sacs and alveolar ducts, and to a lesser extent in respiratory bronchioles
the lung alveoli are said to have a total surface area of over 70m^2 - 11Give three anatomical features of the conducting airwaysciliated pseudo-stratified columnar (or simple columnar) epithelium
cartilage/smooth muscle (varies with level)
glands (sero-mucous, sub-mucosal) - 12What is the volume of the conducting airways? What happens when you breathe out?150-200ml
you have to breathe out the volume of the conducting airways first before you exhale alveolar gas
(sometimes called dead space gas) - 13What volume of gas is exhaled during normal breathing? What is the volume of the conducting airways called?The volume of gas you exhale during normal breathing is about 0.5-1.0 litre. Only the last 350 ml or so comes from the alveoli; at least the first 150 ml is from the conducing airways and is dead space gas
The volume of the conducting airways is called anatomical dead space - 14What may individuals with lung disease have?functional dead space
-if some parts of the lung are not perfused with blood, then they do not contribute to gas exchange. They add to the effective dead space. The total dead space including non-perfused volumes of the lung is the functional/physiological dead space - 15What is bronchoconstriction?narrowing of the airways by the parasympathetic nervous system
reduces dead space but this also increases the resistance of airflow in the lungs
The diameter of the airways during normal breathing is a compromise between having a small dead space (and high flow resistance) and having a larger dead space (and low flow resistance) - 16Wcricoid cartilage
attaches trachea to the thyroid cartilage of the larynx - 17What can be said about the epithelium in the upper airways, lower airways and alveoli? What covers the epithelium?In upper airways there is thicker (more resistant to wear and tear) pseudostratified columnar epithelium. In lower airways simple epithelium. In alveoli the epithelium is very thin to facilitate gas exchange
The epithelium except in the alveoli is covered with a layer of mucus that traps dust and bacteria. Cilia on the epithelium constantly move this mucus upwards to the throat where it is swallowed - 18What do the trachea and main bronchi contain?The trachea and main bronchi contain C-shaped cartilage rings which stiffen the airways and prevent them collapsing
- 19What secretes mucus?mucus is continuously secreted by goblet cells. the mucus is moved up to the pharynx by the cilia in the mucociliary elevator
- 20What are four features of respiratory tissue?Respiratory bronchioles and alveoli (Epithelium is thin-walled to permit gas diffusion)
Type I pneumocytes (squamous, 90% of area)
Type II pneumocytes (cuboidal, 10% of area)
Macrophages, lymphocytes, granulocytes, Mast cells - 21Describe the appearance of lung tissue under a microscopeAlveoli are empty spaces with a thin layer of epithelium
Alveoli are not lined with mucus as this would impede gas exchange. Instead, they contain immune system cells (macrophages& lymphocytes) to combat inhaled pathogens. These cells can move around the inside of the alveolus - 22What are the small holes in the alveolar wall and what is their function?The small holes in the alveolar walls are the pores of Kohn. These are pores between adjacent alveoli. They function as a means of collateral ventilation between alveoli
- 23What structures run around the margin of the alveoli?capillaries
- 24Where are septal cells found? What are they also known as? What do they produce? What is this?Septal cells are found in the septa between alveoli
These cells are also known as type II pneumocytes or type II alveolar cells
These cells produce surfactant
This is a phospholipoprotein dissolved in a watery secretion that lines the alveolar sac. It reduces the surface tension in the alveoli and stops the alveoli collapsing during expiration - 25What is an alveolar macrophage?An alveolar macrophage or ‘dust cell’ is a type of macrophage found in the alveolus. These cells collect dust and other particles in the air and keep the alveoli clean. They often contain granules of exogenous material such as carbon or soot particles. Such black granules may be especially common in smoker's lungs or long-term city dwellers
- 26What do the partial pressures of respiratory gases determine? How can pp be calculated? Calculate the pp of oxygenhow much gas enters of leaves the bloodstream
Partial pressure of gas (A) = total pressure in gas mixture x fractional concentration of (A)
In dry inspired air, the partial pressure of O2 can be calculated as follows. Assume that total pressure is atmospheric and the fractional concentration of O2 is 0.21
PO2 = 760 mm Hg x 0.21 = 160 mm Hg - 27Water vapour is added to inspired gas as it moves through the mouth or nasopharynx. Calculate the pp of oxygen in tracheal airTo find the partial pressure of oxygen in tracheal air, the calculation is modified to correct for the partial pressure of H20 (= 47 mmHg)
P total = 760 mmHg - 47 mmHg = 713 mm Hg
PO2 = 713 mm Hg x 0.21 = 150 mm Hg - 28In a healthy individual what is the pp of oxygen and carbon dioxide in the alveoli?Partial pressure of oxygen in the alveoli in a healthy person is about 100 mm Hg.
Partial pressure of CO2 is about 40 mm Hg - 29What happens to oxygen fraction and total pressure at altitude?At altitude oxygen fraction stays constant but total pressure decreases; therefore oxygen partial pressure decreases. Respiratory rate and/or depth must be increased to compensate
- 30Describe the impact of respiratory diseaseIn 2001, approximately 8.3% of all deaths in London were from respiratory disease, mainly pneumonia, bronchitis and emphysema.
In the UK, approximately 1 in 7 individuals are affected by some form of chronic lung disease, most commonly chronic obstructive pulmonary disease, which includes asthma, chronic bronchitis and emphysema - 31Give six examples of respiratory diseases and infectionsAsthma
COPD (chronic bronchitis and emphysema, etc.)
Tumours (Carcinoma of the lung, mesothelioma, etc.)
Pulmonary fibrosis (including fibrosing alveolitis)
Occupational lung disease (silicosis, pneumoconiousis, asbestosis)
Disorders of chest wall, pleura and diaphragm (eg pneumothorax) - 32What are four notable respiratory diseases and infections?Common cold (acute coryza)
Influenza
Pneumonia (viral, bacterial and fungal)
Pulmonary tuberculosis - 33Acute viral respiratory illnesses are among the most common of human diseases. Give three facts about themThey account for one-half or more of all acute illnesses
Are the most common manifestation of respiratory illness: the "common cold"
may also manifest as pharyngitis, croup, tracheitis, bronchitis, and pneumonia - 34What are five common infectious viruses?rhinovirus
coronavirus
respiratory syncytial virus (RSV)
parainfluenza virus
adenovirus - 35What are four social factors affecting respiratory diseasePoor housing, nutrition and income (eg TB)
Smoking (COPD and CA-lung)
Travel (TB, etc.)
STDs and iv drug abuse (HIV, TB/pneumonia, etc.) - 36What are two environmental factors that affect respiratory disease?Air pollution, especially particulates and SO2 (COPD/asthma)
House dust mites (asthma) - 37What are two occupational factors that affect respiratory disease?dust and chemical exposures
allergies
-asbestosis
-mesothelioma
-silicosis
-pneumonconiosis
-pulmonary fibrosis
-fibrosing alveolitis
Informações
- Descrição
- University Cardiorespiratory FlashCards sobre 22 Introduction to the Respiratory System, criado por Ifeoma Ezepue em 13-01-2016.
- Criado por
- Ifeoma Ezepue
- Visualizações
- 8
- Avaliação